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We have investigated an insertion process of conjugated molecules, 4-biphenylmethanethiol (BP) and [1,1′:4′,1″-terphenyl]-4-methanethiol (TP) into preassembled n-alkanethiol self-assembled monolayers on Au(111) using scanning tunneling microscopy (STM). Ex situ STM observation revealed that the insertion process is dependent on an organic solvent in which the conjugated molecules dissolve. The insertion of conjugated molecules with three phenyl rings (TP) was faster than that with two phenyl rings (BP). By analyzing the STM images, the lower limits of resistances for single BP and TP molecules were obtained as 22±5 and 36±5 GΩ, respectively.

Atomic force microscopy was employed to analyze the electric double layer on an Au film electrode deposited on mica. An Au‐covered or a bare Si3N4 tip was used as a probe. An electrolyte solution was aqueous NaOH of pH 10.9. The electrode and the tip potentials were controlled electrochemically by a potentiostat. Repulsive forces were always observed regardless of the polarity of the potential, i.e., the positive and the negative side of the point of zero charge. The result indicates that the strongly adsorbed OH− anions overcompensated the positive charge at the Au surface. The potential of the outer Helmholtz plane at an electrode potential was estimated from the force–distance curves.

We observed two types of stearic acid single crystals having different lattice constants with a friction force microscope to study the molecular scale friction. Molecularly resolved friction force microscope images and molecularly periodic stick‐slip motions of the cantilever were observed. The stick‐slip motion of the cantilever was measured in terms of the normal load acting on the silicon nitride cantilever and scanning directions over the single crystals.

We describe the study of a chemically modified quartz surface by atomic force microscopy and friction force microscopy. The chemically modified surface was covered with hydrocarbon (HC) and fluorocarbon (FC) in different parts. The region selective surface chemical modification with two different silanization reagents was successfully accomplished by the following procedure: exposed quartz surfaces of a quartz plate covered with microlithographically prepared patterns of chromium film were first modified with one of the silanization reagents, then the patterns of chromium film were etched, and finally, newly exposed quartz surfaces were modified with the other silanization reagent. The chemical modification with such etching allowed patterning with a submicrometer scale. Since the location of the surfaces covered with two different chemical species was known in the chemically modified surfaces, assignment of the measured frictions to the individual surfaces was definite. The relative values of the differe...

In this paper we describe the structural study of Langmuir–Blodgett (LB) films with a scanning surface potential microscope (SSPM) together with an ordinary atomic force microscope (AFM). The SSPM is a new type of high‐resolution potentiometry due to electrostatic force microscopy and is a member of the AFM family. Our SSPM is a modified Kelvin probe force microscope, and is based upon the design of a recently developed scanning Maxwell stress microscope (SMM). This microscope can be used to study distribution of the surface potential or the contact potential difference (CPD) with submicrometer spatial resolution. We have applied this microscope to the study of molecular orientation of amphiphilic molecules in LB films. The surface dipole moments due to the terminal CH3 group of the long alkyl chain and the hydrophilic head group are used to study the orientation in the multilayered structures of LB films. In the present work, we focused on reorientation of the amphiphilic molecules in LB films during monolayer transfer and by oxidation of the substrate surface.

An atomic force microscopy study is presented on lubricating systems, such as thin organic Langmuir–Blodgett films. Local elastic compliance was measured simultaneously with topography and friction on thin films of mixtures of fluorocarbons and hydrocarbons. On the phase‐separated fluorocarbon domains, higher friction and lower Young’s modulus than on the hydrocarbon domains was found. Adhesive wear has been observed to occur randomly on the stiffer hydrocarbon domains if the film is complexed with a counterion polymer of a larger cross‐sectional area. A quantitative fractal analysis of the hydrocarbon film remaining areas provided a linear adhesive wear dependence on the scan cycle number.

We describe the study of microlithography of a thin chromium film on a quartz plate by an atomic force microscope (AFM) and a friction force microscope (FFM). The scratching of Langmuir–Blodgett (LB) films of ω‐tricosenoic acid deposited on the chromium films was carried out by scanning an AFM tip under a high normal force of ∼5×10−8 N. The scratched depth was measured by a topographic AFM image recorded by scanning with a new tip under a low normal force of 1×10−8 N. The surface properties of the scratched surfaces created in the multilayered LB films were studied by the FFM. From (1) the wear patterns observed on the scratched surface of the multilayer and (2) the high resistance against scratching of the single monolayer observed by AFM and FFM, it was concluded that the first monolayer always remained even after scratching under the high normal force. Etching resistance of the chromium surfaces covered with LB films with a various number of monolayers was also studied by measuring elapsed times requir...